Supportive but not challenging - Grad Scheme Archetype Employee Review

My progression was held back and stinted when I asked to move up to an Account Executive position. Despite the colleagues around me telling me I was already working at well above my level, my manager insisted I wasn't ready and wanted to keep me on a grad salary with the same title, I didn't feel my progression was supported, and when looking elsewhere was offered plenty of AE level roles based on my experience.